Frequency hop sequence discovery mechanism

ABSTRACT

An apparatus including narrowband receivers and a controller. The narrowband receivers are deployed geographically within a grid, where each of the narrowband receivers is configured to receive transmissions from a least one of a plurality of automated meter reading (AMR) meters, and where each of the plurality of AMR meters transmits identical data on each of a plurality of frequency bands that are hopped according to an unknown hopping sequence, but a known hop rate. The controller is coupled to the narrowband receivers, and is configured to control the narrowband receivers such that the each of the plurality of AMR meters is identified, and is configured to control the narrowband receivers such that corresponding data from the each of the AMR meters is received on at least one of the plurality of frequency bands.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of the following U.S. Nonprovisionalpatent application, which is herein incorporated by reference for allintents and purposes.

SER. FILING NO. DATE TITLE 13/617,782 Sep. 14, 2012 APPARATUS AND METHODFOR (ENER.0106) RECEIVING AND TRANSPORTING REAL TIME ENERGY DATA

The above noted U.S. Nonprovisional patent application claims thebenefit of the following U.S. provisional application, which is hereinincorporated by reference for all intents and purposes.

SER. FILING NO. DATE TITLE 61/534,503 Sep. 14, 2011 WIRELESS NETWORK(ENER.0106) EXTENSIONS FOR ENERGY MANAGEMENT AND DEMAND CONTROL

This application is related to the following co-pending U.S.Nonprovisional patent applications.

FILING SER. NO. DATE TITLE 13/025,142 Feb. 10, 2011 APPARATUS AND METHODFOR DEMAND (ENER.0101) COORDINATION NETWORK 13/864,933 Apr. 17, 2013DEMAND COORDINATION NETWORK CONTROL (ENER.0101-C1) NODE 13/864,942 Apr.17, 2013 APPARATUS AND METHOD FOR CONTROLLING (ENER.0101-C2) PEAK ENERGYDEMAND 13/864,954 Apr. 17, 2013 CONFIGURABLE DEMAND MANAGEMENT SYSTEM(ENER.0101-C3) 13/032,622 Feb. 22, 2011 APPARATUS AND METHOD FORNETWORK-BASED (ENER.0103) GRID MANAGEMENT 13/601,622 Aug. 31, 2012NOC-ORIENTED CONTROL OF A DEMAND (ENER.0105) COORDINATION NETWORK14/547,919 Nov. 19, 2014 NETWORK LATENCY TOLERANT CONTROL OF A(ENER.0105-C1) DEMAND COORDINATION NETWORK 14/547,962 Nov. 19, 2014APPARATUS AND METHOD FOR PASSIVE (ENER.0105-C2) MODELING OF NON-SYSTEMDEVICES IN A DEMAND COORDINATION NETWORK 14/547,992 Nov. 19, 2014APPARATUS AND METHOD FOR ACTIVE MODELING (ENER.0105-C3) OF NON-SYSTEMDEVICES IN A DEMAND COORDINATION NETWORK 14/548,023 Nov. 19, 2014APPARATUS AND METHOD FOR EVALUATING (ENER.0105-C4) EQUIPMENT OPERATIONIN A DEMAND COORDINATION NETWORK 14/548,057 Nov. 19, 2014 APPARATUS ANDMETHOD FOR ANALYZING (ENER.0105-C5) NORMAL FACILITY OPERATION IN ADEMAND COORDINATION NETWORK 14/548,097 Nov. 19, 2014 APPARATUS ANDMETHOD FOR MANAGING (ENER.0105-C6) COMFORT IN A DEMAND COORDINATIONNETWORK 14/548,107 Nov. 19, 2014 DEMAND COORDINATION SYNTHESIS SYSTEM(ENER.0105-C7) 14/691,858 Apr. 21, 2015 NOC-ORIENTED DEMAND COORDINATION(ENER.0105-C8) NETWORK CONTROL NODE 14/691,907 Apr. 21, 2015NOC-ORIENTED APPARATUS AND METHOD FOR (ENER.0105-C9) CONTROLLING PEAKENERGY DEMAND 14/691,945 Apr. 21, 2015 CONFIGURABLE NOC-ORIENTED DEMAND(ENER.0105-C10) MANAGEMENT SYSTEM 14/729,907 Jun. 3, 2015 APPARATUS ANDMETHOD FOR RECEIVING AND (ENER.0106-C1) TRANSPORTING REAL TIME AMR METERDATA 14/729,963 Jun. 3, 2015 REAL TIME ENERGY DATA TRANSPORT MECHANISM(ENER.0106-C2) 14/730,007 Jun. 3, 2015 LOW-COST REAL TIME ENERGY DATATRANSPORT (ENER.0106-C3) APPARATUS AND METHOD         — MESH NETWORKTOPOLOGY ASSESSMENT (ENER.0106-C4 MECHANISM         — APPARATUS ANDMETHOD FOR END-TO-END LINK (ENER.0106-C5) QUALITY INDICATION

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates in general to the field of automated resourcecontrol, and more particularly to a topology assessment mechanism fordeploying and maintaining wireless networks.

2. Description of the Related Art

Since late in the 1800's, electrical power, natural gas, and waterproviders have been distributing these resources to consumers. And notlong after larger distribution grids were deployed by these utilities,the problem of billing based upon consumption arose. Consequently,utilities began to install consumption meters for these resources attheir respective points of consumption.

Accordingly, virtually everyone in this country and many countriesabroad understand the role of the “meter reader,” for early utilitymeters provided only a visual indication of how much certain resourcehad been consumed over a billing period. Thus, in order for a resourceprovider to determine the amount of that resource which had beenconsumed over a billing period, it was necessary to dispatch personneleach time a meter reading was required. This typically occurred on amonthly basis.

This manner of obtaining usage data, however, was labor intensive andconsequently very costly. In addition, because the act of reading ameter involved interpretation of the meaning of one or more visualindicators (typically analog indicators like the hands on a watch),these readings were subject to inaccuracies due to errors made by themeter readers.

In the past twenty years, developers have begun to address the problemsof labor cost and inaccurate readings due to the human element byproviding so-called automatic meter reading (AMR) meters, the mostprevalent type of which broadcast their current values in a known andencoded low power radio frequency transmission capable of being capturedby a corresponding AMR receiver in a moving vehicle. Hence, AMRtechnologies substantially alleviate the limitations of former metersrelated to accurate readings and markedly addressed the cost of laborrequired to read meters.

But in order to deploy AMR products, the resource providers had tocompletely replace their existing inventory of meters—literally hundredsof millions of meters—at substantial expense, the bulk of which wasconveyed either directly or indirectly to consumers.

In the past ten years, developers have responded to demands in the artfor so-called “smart meters,” that is, meters that allow for two-waycommunication between a resource provider and a point of consumption.Two-way communications between a provider and a meter, also known asautomated metering infrastructure (AMI) yields several benefits to theprovider because with AMI the provider is no longer required to send outpersonnel to control consumption at an access point. With AMI meters, autility can turn on and turn off consumption of the resource at theconsumption point without sending out service personnel. And what ismore attractive from a provider standpoint is that AMI techniques can beemployed to perform more complex resource control operations such asdemand response control.

The present inventors have observed, however, that to provide for AMI,under present day conditions, requires that the utilities—yet one moretime—replace their entire inventory of AMR meters with more capable, andsignificantly more expensive, AMI meters. In addition, present dayapproaches that are directed toward providing the two-way communicationsbetween the utilities and their fleet of AMI meters all require thedevelopment of entirely new communications infrastructures (e.g., Wi-Fi,satellite) or they are bandwidth limited (e.g., cellular).

Consequently, what is required is an apparatus and method for providingAMI capabilities to existing AMR meters without a requirement toentirely replace or significantly modify the existing AMR meters.

In addition, what is required is a mechanism for deploying an AMI gridthat minimizes the cost of metering and two-way communications upgrades.

Furthermore, what is needed is a smart grid technique that employsexisting AMR meters and moreover leverages already deployed highbandwidth two-way communications infrastructures.

Moreover, what is needed is a cost-effective mechanism for readingexisting AMR meter grids.

Further, what is needed is a technique that supports the deployment ofwireless devices in a manner that security provisions are tailoredaccording to proximity.

Also, what is needed is a topology assessment mechanism for deployingand maintaining wireless networks.

In addition, what is needed is a technique that allows end-to-end linkquality in a wireless network to be easily quantified.

Furthermore, what is needed is a method for discovering a frequencyhopping sequence in a system of devices such as AMR meters.

Moreover, what is needed is a large payload fragmentation scheme for useby a network of wireless devices.

Also, what is needed is a mechanism whereby a mesh network of wirelessdevices may optimally select bands/channels for transmission of messagesto other devices in the network.

SUMMARY OF THE INVENTION

The present invention, among other applications, is directed to solvingthe above-noted problems and addresses other problems, disadvantages,and limitations of the prior art. The present invention provides asuperior technique for receiving and transporting real time resourceusage data corresponding to a grid of resource usage devices that employa frequency hopping algorithm to broadcast usage data. In oneembodiment, an apparatus is provided for receiving and transporting realtime resource usage data. The apparatus includes a plurality ofnarrowband receivers and a controller. The plurality of narrowbandreceivers is deployed geographically within a grid, where each of theplurality of narrowband receivers is configured to receive transmissionsfrom a least one of a plurality of automated meter reading (AMR) meters,and where each of the plurality of AMR meters transmits identical dataon each of a plurality of frequency bands that are hopped according to ahopping sequence, and where the hopping sequence is initially unknown tothe plurality of narrowband receivers, but a hop rate is known. Thecontroller is coupled to the plurality of narrowband receivers, and isconfigured to control the plurality of narrowband receivers such thatthe each of the plurality of AMR meters is identified, where thecontroller determines the frequency hopping sequence by progressivelyselecting channel candidate pairs from a list of channels for thefrequency hopping sequence, and determines adjacent channel pairs in thelist of channels based upon latency of messages having the identicaldata observed between the channel candidate pairs according to the hoprate.

Another aspect of the present invention contemplates an apparatus forreceiving and transporting real time resource usage data. The apparatushas a plurality of narrowband receivers, a controller, and a networkoperations center (NOC). The plurality of narrowband receivers isdeployed geographically within a grid, where each of the plurality ofnarrowband receivers is configured to receive transmissions from a leastone of a plurality of automated meter reading (AMR) meters, and whereeach of the plurality of AMR meters transmits identical data on each ofa plurality of frequency bands that are hopped according to a hoppingsequence, and where the hopping sequence is initially unknown to theplurality of narrowband receivers, but a hop rate is known. Thecontroller is coupled to the plurality of narrowband receivers, and isconfigured to control the plurality of narrowband receivers such thatthe each of the plurality of AMR meters is identified, and is configuredto control the plurality of narrowband receivers such that correspondingdata from the each of the AMR meters is received on at least one of theplurality of frequency bands, where the controller determines thefrequency hopping sequence by progressively selecting channel candidatepairs from a list of channels for the frequency hopping sequence, anddetermines adjacent channel pairs in the list of channels based uponlatency of messages having the identical data observed between thechannel candidate pairs according to the hop rate. The NOC isoperatively coupled to the controller via an existing infrastructure,and is configured to receive the real time resource usage data from thecontroller.

A further aspect of the present invention comprehends a method forreceiving and transporting real time resource usage data. The methodincludes deploying a plurality narrowband receivers within a grid,wherein each of the plurality of narrowband receivers is configured toreceive transmissions from a least one of a plurality of automated meterreading (AMR) meters, and wherein each of the plurality of AMR meterstransmits identical data on each of a plurality of frequency bands thatare hopped according to a hopping sequence, and wherein the frequencyhopping sequence is initially unknown to said plurality of narrowbandreceivers, but a hop rate is known; and controlling the plurality ofnarrowband receivers such that the each of the plurality of AMR metersis identified, and that corresponding data from the each of the AMRmeters is received on at least one of the plurality of frequency bands,wherein the controller determines the frequency hopping sequence byprogressively selecting channel candidate pairs from a list of channelsfor the frequency hopping sequence, and determines adjacent channelpairs in the list of channels based upon latency of messages having theidentical data observed between said channel candidate pairs accordingto the hop rate.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other objects, features, and advantages of the presentinvention will become better understood with regard to the followingdescription, and accompanying drawings where:

FIG. 1 is a block diagram illustrating a present day automatic meterreading technique;

FIG. 2 is a block diagram depicting a present day automatic meteringinfrastructure;

FIG. 3 is a block diagram featuring a grid management system accordingto the present invention;

FIG. 4 is a block diagram showing a slave interface mechanism accordingto the present invention such as might be employed in the gridmanagement system of FIG. 3;

FIG. 5 is a block diagram illustrating a master interface mechanismaccording to the present invention such as might be employed in the gridmanagement system of FIG. 3;

FIG. 6 is a block diagram detailing a wireless slave interface mechanismaccording to the present invention such as might be employed in the gridmanagement system of FIG. 3;

FIG. 7 is a block diagram showing a wireless master interface mechanismaccording to the present invention such as might be employed in the gridmanagement system of FIG. 3; and

FIG. 8 is a block diagram depicting topology-adaptive networkingaccording to the present invention.

FIG. 9 is a block diagram illustrating an apparatus for receiving andtransporting real time energy data according to the present invention;

FIG. 10 is a flow diagram depicting a method employed by the apparatusof FIG. 9 to identify meters based upon received messages;

FIG. 11 is a flow diagram featuring a method employed by the apparatusof FIG. 9 to determining a hop sequence for identified meters;

FIG. 12 is a flow diagram showing a method employed by the apparatus ofFIG. 9 for assigning receiver channels in order to ensure optimal metercoverage;

FIG. 13 is a block diagram illustrating a proximity based wirelesssecurity mechanism according to the present invention;

FIG. 14 is a flow diagram detailing a technique employed by the securitymechanism of FIG. 13 to allow or prevent devices from joining a network;

FIG. 15 is a block diagram showing a mesh network topology assessmentmechanism according to the present invention;

FIG. 16 is a flow diagram depicting a method employed by the mechanismof FIG. 15 to assess the topology of a mesh network;

FIG. 17 is a block diagram illustrating a technique according to thepresent invention for determining a network level received signalstrength indication (RSSI);

FIG. 18 is a flow diagram depicting a method according to the presentinvention for discovering the frequency hopping sequence correspondingto a network of devices;

FIG. 19 is a block diagram featuring an apparatus according to thepresent invention for simultaneously fragmenting and transmitting largepacket payloads;

FIG. 20 is a block diagram showing a multi-band communications networkaccording to the present invention;

FIG. 21 is a flow diagram illustrating a method employed by the networkof FIG. 20 to select transceivers for FIG. 22 is a block diagramdetailing an exemplary descriptor stores such as may be employed indevices within the network of FIG. 20.

DETAILED DESCRIPTION

Exemplary and illustrative embodiments of the invention are describedbelow. In the interest of clarity, not all features of an actualimplementation are described in this specification, for those skilled inthe art will appreciate that in the development of any such actualembodiment, numerous implementation-specific decisions are made toachieve specific goals, such as compliance with system related and/orbusiness related constraints, which vary from one implementation toanother. Furthermore, it will be appreciated that such a developmenteffort might be complex and time-consuming, but would nevertheless be aroutine undertaking for those of ordinary skill in the art having thebenefit of this disclosure. Various modifications to the preferredembodiment will be apparent to those skilled in the art, and the generalprinciples defined herein may be applied to other embodiments.Therefore, the present invention is not intended to be limited to theparticular embodiments shown and described herein, but is to be accordedthe widest scope consistent with the principles and novel featuresherein disclosed.

The present invention will now be described with reference to theattached figures. Various structures, systems, and devices areschematically depicted in the drawings for purposes of explanation onlyand so as to not obscure the present invention with details that arewell known to those skilled in the art. Nevertheless, the attacheddrawings are included to describe and explain illustrative examples ofthe present invention. The words and phrases used herein should beunderstood and interpreted to have a meaning consistent with theunderstanding of those words and phrases by those skilled in therelevant art. No special definition of a term or phrase, i.e., adefinition that is different from the ordinary and customary meaning asunderstood by those skilled in the art, is intended to be implied byconsistent usage of the term or phrase herein. To the extent that a termor phrase is intended to have a special meaning, i.e., a meaning otherthan that understood by skilled artisans, such a special definition willbe expressly set forth in the specification in a definitional mannerthat directly and unequivocally provides the special definition for theterm or phrase.

In view of the above background discussion on automatic meter readingand associated techniques employed by present day resource providers toobtain meter readings from resource consumers, a discussion of thelimitations and disadvantages of these techniques will now be presentedwith reference to FIGS. 1-2. Following this, a discussion of the presentinvention will be provided with reference to FIGS. 3-22. The presentinvention overcomes the noted limitations and disadvantages of presentday automatic meter reading mechanisms by providing apparatus andmethods that enable cost effective reception and transport of real timeusage data over an existing communications infrastructure withoutrequiring replacement of existing meters, thereby providing for theelimination of fleet assets associated with obtaining usage data,providing continuous and more reliable communications, and obtainingmaximum benefit from previous capital outlays.

Turning to FIG. 1, a block diagram 100 is presented illustrating apresent day automatic meter reading technique. The diagram 100 showsexemplary structures 101 that employ a consumable resource that isproduced or provided by a resource provider. Coupled to each of thestructures 101 is a corresponding resource meter 102 that is configuredto measure usage of the resource over a particular time period forpurposes of billing consumers associated with the structures 101. Assuch, the meters 102 are certified to provide billing grade data. Thatis, their accuracy and sampling frequencies of resource consumption areadequate for billing purposes, but are not fast enough to allow foranalysis of how a particular structure 101 may utilize the resource overa shorter period of time. The meters 102 are operationally coupled tothe resource itself and perform measurements commensurate with thebilling requirements of the resource provider. It is noted thatpresently such meters 102 exist to measure consumption of electricalpower (electricity), natural gas, and water, but the present inventorsnote that the discussion of the present invention hereinafter is not tobe constrained to the aforementioned resources. Rather, the presentinvention contemplates measurement and control of any conceivable andmeasurable resource such as, but not limited to, air, any form ofgaseous substance, nuclear power, liquid resources, solid resources, andthe like, which may benefit from metered measurement, reporting, andcontrol. Hereinafter, since meters 102 of the sort noted above are mostprevalently employed within the electrical power field, the followingexamples will be discussed in terms well known to those conversant inthe areas of electrical power generation, distribution, and consumption.Yet, it is noted that such terminology is employed only as a convenientvehicle to clearly teach aspects of the present invention and thepresent invention should not be restricted in scope in any way tospecific application within the electrical power field.

Older meters (not shown) provided some form of visual indication ofelectrical power consumption, and personnel (i.e., meter readers) weredispatched typically monthly to each building within an electrical powerprovider's service area (i.e., grid) to manually obtain readingsassociated therewith. This approach was naturally labor intensive andthus expensive. In addition, because the accuracy of the data obtaineddepended on human factors, such an approach was subject to error.

Many electrical power providers today utilize automatic meter readingmeters 102 that periodically broadcast their respective readings overrelatively secure wireless communication links 105. A significant numberof AMR meters 102 today employ an encoded receiver transmitter (ERT)technique to broadcast encoded meter readings over the communicationlinks 105. To obtain these readings, the electrical power providertypically dispatches a vehicle 103 that is equipped with an antenna 104and associated receiver (not shown) that is configured to automaticallyreceive, identify, and store the readings from each of the meters 102.ERT is a low power wideband (i.e., frequency hopping) radio frequency(RF) technique that is widely used for automatic meter reading, but itstill requires the dispatch of personnel and equipment in order togather consumption data from the AMR meters 102. Accordingly, while theaccuracy of data obtained through the use of AMR meters 102 is improvedover manual approaches, gathering of consumption data is still costlybecause of the personnel and equipment that are still required to do so.Moreover, AMR meters 102 are one-way communication devices and are thusincapable of serving as a control mechanism responsive to a resourceprovider's requirements. For example, in order to cut off power to aparticular building 101, the provider must dispatch service personnelwho manually cut off the power to the particular building 101. Thus, itis impossible for AMR meters 102 to be employed in more sophisticatedresource provider programs such as demand response control and the likein any way that does not require the dispatch of personnel.

A number of more recent initiatives are planned to address the one-wayand manual limitations of AMR-based grid systems, which include the useof two-way communications provided by so-called “smart meters.” Thereare a number of different two-way communication technologies that areemployed by these smart meters, to include spread spectrum RF, wirelessmesh, Wi-Fi, and power line communication (PLC). These smart meters andtheir associated infrastructures, regardless of their correspondingcommunication technology, are commonly referred to in the art asautomated metering infrastructure (AMI), an example of which will now bediscussed with reference to FIG. 2.

Turning to FIG. 2, a block diagram is presented depicting an exemplarypresent day automatic metering infrastructure (AMI) 200. The AMI 200provides for a plurality of AMI meters 202, 204, each of which iscoupled to a corresponding structure 201, like the structures 101 ofFIG. 1. In this example, the meters 202, 204 provide for two-waycommunication over wireless communication links 203 configured as awireless mesh. Metering data is passed from one AMI meter 202 to thenext 202 over the mesh network, and the various data streams arrive atan endpoint AMI meter 204 which functions to relay the aggregated meterreadings to a local aggregation point 207. The aggregation point 207 istypically configured with an antenna 206, receiver (not shown), andstores (not shown) adequate to provide for local reception and temporarystorage of metering data. The aggregation point 207 is additionallyconfigured to transmit the aggregated metering data over a higher speedcommunications link 208 back to the resource provider. Various types ofcommunication link technologies are employed to couple the aggregationpoint 207 to the resource provider, including the technologies notedabove with reference to smart meter communications. Cellular (i.e.,wireless cell phone) communications are commonly employed to provide forthe communication link (also referred to as a “backhaul link”) 208.

Operationally, the AMI meters 202, 204, are configured to provide fortwo-way communications within a limited area to provide the resourceprovider with metering data and to also allow for control of theresource for particular facilities 201. In the wireless mesh exampleshown, one skilled in the art will appreciate that because wirelesstransceivers within the AMI meters 202, 204 are low power by design,there is often a requirement to supplement the mesh network by theaddition of a repeater 205, which is employed to amplify signals thathave been attenuated as a result of propagation distance, propagationpath blockage, or interference.

AMI is effective in overcoming the one-way limitations of former AMRsystems. As a result, many utilities are currently replacing AMR meters102 with newer, more capable AMI meters 202, 204. But the presentinventors have observed that AMI meters 202, 204 are significantly moreexpensive than currently deployed AMR meters 102. Stated differently, inorder to upgrade a given area within a grid to provide for AMI, it isnecessary to completely replace all of the AMR meters 102 in the areawith more expensive AMI meters 202, 204. In addition, aggregation points207 and associated backhaul communications 208 must be deployed toenable two-way communications between the new AMI meters 202, 204 andthe resource provider.

Accordingly, the present inventors have observed that resource providershave a tremendous capital investment in AMR meters 102, which comprisesa significant portion of the costs associated with distribution, and toreplace these AMR meters 102 with newer and more expensive AMI meters202, 204 requires yet another costly capital outlay. The presentinventors have also noted that the burdensome expense of upgrading anexisting AMR grid to provide for AMI capabilities is disadvantageous atbest because ultimately the consumer will be paying for the cost ofthese upgrades, either directly (in terms of increased cost of theresource) or indirectly (through demand limitations and consumptioncaps).

In addition to the above, the present inventors have noted that toprovide backhaul communications 208 from the aggregation point 207 tothe resource provider, all present day implementations of AMI typicallyrequire an entirely new and costly high bandwidth communicationsinfrastructure 208, the cost of which is also passed on to consumers.Lower speed communications infrastructures exist, such as using cellularand satellite communications as the link 208, but these approaches arebandwidth limited and thus restrict the number of AMI functions that canbe performed because the amount and frequency of data that can betransmitted over the link 208 is limited.

The present invention overcomes the above noted limitations, and others,by providing apparatus and methods whereby an existing AMR grid isupgraded to provide for AMI capabilities and additional functionsthrough slight modification to the existing AMR meters 102, therebyeliminating the replacement cost of these meters 102. In addition, thepresent invention utilizes a significant portion of an existing backhaulinfrastructure, thereby simplifying communications between a meteredarea and a resource provider. The present invention will now bediscussed with reference to FIGS. 3-22.

Now referring to FIG. 3, a block diagram is presented featuring a gridmanagement system 300 according to the present invention. The system 300includes a plurality of structures 304 like those 101, 201 of FIGS. 1-2that consume a resource that is provided and metered by a resourceprovider. In one embodiment the resource comprises electricity. Inanother embodiment, the resource comprises natural gas. A thirdembodiment contemplates water as the resource. Other embodiments arecomprehended as well that comprise other consumable resources as hasbeen described above. Each of the structures 304 is with equipped withan existing AMR meter 307, like the meters 102 of FIG. 1. One of themeters 307 in a given area is coupled to a master interface device 310.The remainder of the meters 307 in the given area are each coupled to aslave interface device 311. In one embodiment, the meters 307 comportwith requirements prescribed by the ANSI C.12 series of specifications.In another embodiment, the meters 307 fall into the category of standardAMR meters, an example of which is the i210 AMR meter produced byGENERAL ELECTRIC®. In one embodiment, the master interface device 310and slave interface devices 311 comprise an easily attachable adaptersuch as a meter collar or the like, as is well known by those skilled inthe art. In a second embodiment, the master interface device 310 andslave interface devices 311 comprise circuit cards that are insertedinto available slots within the AMR meters 307. An alternativeembodiment contemplates a master interface device 310 and slaveinterface devices 311 that are separate from but collocated with theircorresponding meters 307 within a range that is commensurate withreception of AMR data transmitted by the AMR meters 307.

The master device 310 is coupled to all of the slave devices 311 via acommunications link 309. In one embodiment, the communications link 309comprises a wired variable speed serial data link 309 configured as astar network. In a wireless embodiment, the communications link 309comprises a wireless mesh network.

One embodiment of the grid system 300 contemplates employment of anexisting communications infrastructure 301 that couples thecommunications link 309 to a network operations center 303. The networkoperations center (NOC) 303 provides for monitoring and control of theresource to each of the facilities 304 through commands and datatransmitted and received over a command link 306 that couples theexisting communications infrastructure 301 to a high speed data device305. The high speed data device 305 is coupled to the master device 310and the master device 310 provides for monitoring and control of all theslave devices 311 coupled thereto via commands and data transmitted andreceived over the communications link 309.

One embodiment of the present invention contemplates an existing publictelephone network 301, which includes wiring pedestals 302 that provideconnectivity of the network 301 to each of the facilities 304. As oneskilled in the art will appreciate, a typical existing drop from apedestal 302 to a facility 304 comprises multiple conductors that areavailable for connections. According to this embodiment, the conductorsmay comprise copper or other metal wire, coaxial cable, fiber-opticcable, and any other form of fixed transmission media. Additionally, forspecialized installations such as those in extremely dense areas,extremely rural areas, and widely-spaced areas, and for installationsthat preclude utilizing a wire to provide the short distance local areanetwork, a point-to-point secure wireless bridge is also contemplated asthe communication link 309.

Another embodiment of the present invention considers an existing cableinfrastructure 301 such as is employed to provide television andInternet connectivity to the structures 304. Accordingly, the pedestals302 may be deployed above ground on poles or underground.

According to any of the above embodiments, it is noted that the commandlink 306 couples the local grid to the NOC 303 by utilizing a high speeddevice 305 that is compatible with the existing infrastructure 301. Inthe case of a public switched telephone network infrastructure 301, thehigh speed device 305 comprises a digital subscriber line (DSL) modem305. In the case of a cable-based infrastructure 301, the high speeddevice 305 comprises a cable modem 305.

In wired embodiments, the communication link 309 comprises a starnetwork where the coupling point is within an existing pedestal 302 orsubstantially similar cross connect terminal. In wireless embodiments,the pedestal 302 or substantially similar cross connect terminal isemployed solely to provide connectivity of the high speed device 305 tothe existing infrastructure 301 via the command link 306. In wirelessembodiments, the master interface device 310 may be coupled to the highspeed device 305 via a wireless link or a wired link.

In operation, each of the slave interface devices 311 and the masterinterface device 310 are configured to gather data from theircorresponding existing AMR meter 307 via either a wired or wirelessinterface. The master interface device 310 adaptively configures thedata rate of the communications link 309 to enable reliable andefficient transfer of data to/from each of the slave devices 311according to the propagation lengths that are exhibited by the existinginfrastructure 301. As one skilled in the art will appreciate, aresidential deployment of telephone or cable connects anywhere from oneto greater than ten structures 304 within a single pedestal 302. Thus,the propagation path from the master interface device 310 to individualslave devices 311 may vary by greater than a factor of ten.Advantageously then, the variable speed communication link 309 that isadaptively configured by the master interface device 310 to the slaveinterface devices 311 within a given grid enables additional slavedevices 311 to be added or deleted without a requirement forreprogramming.

Thus, all data that is gathered from the AMR meters 307 within the localgrid is transmitted to the master interface device 310 over thecommunications link 309 and the master interface device 310 transmitsthis data to the NOC 303 via the high speed device 305 that is coupledto the existing infrastructure 301. One embodiment of the presentinvention contemplates master and slave interface devices 310-311 thatare not only capable of gather billing quality data from the AMR meters307, but which are also coupled to the resource itself and are capableof sampling consumption of the resource at a sample rate commensuratewith the analysis of time-varying loads and signatures. This analysisquality data is also transmitted to the NOC 303 via the high speeddevice 305.

In addition to billing and analysis data, the present invention alsocontemplates control of the resource at specified facilities 304 viacommands sent from the NOC 303 and received by the master interfacedevice 310. If applicable, these commands are subsequently routed tospecified slave devices that are coupled to the specified facilities304. Accordingly, a resource provider is enabled to inexpensivelycontrol consumption of the resource at a given facility 304 via commandsgenerated at the NOC 303. This control can range from simple cut-on andcut-off of the resource to scheduled regulation of the resource, such asmight be encountered in an electrical power demand response system.Advantageously, no personnel or equipment need be dispatched to bothmonitor and control resource consumption and existing AMR meters 307 canbe fully utilized.

The present invention enables a private, secure, low cost, highreliability, AMI network solution 300 over existing infrastructure 301that provides utilities and other resource providers with an acceleratedand economical path to deployment of AMI and 2-way communication withoutthe expense of replacement of existing AMR meters 307 with new smartmeters 202, and without the risk of less proven communication methods.

The present invention overcomes the deficiencies of present day AMIapproaches as noted above, and others limitations related toimplementing an AMI network. The present inventors have noted that allpresent known AMI network solutions require a new infrastructure to bebuilt. Thus, it is a feature of the present invention to use an existinginfrastructure 301, which is both ubiquitous and scalable. That is, theexisting infrastructure 301 is architected and built to accommodateevery dwelling 304 under extreme loads with low latency.

The master interface device 310 according to the present invention isconfigured to perform the functions and operations disclosed herein. Themaster interface device 310 comprises logic, circuits, devices, ormicrocode (i.e., micro instructions or native instructions), or acombination of logic, circuits, devices, or microcode, or equivalentelements that are employed to perform the functions and operationsaccording to the present invention. The elements employed to storeperform these functions and operations within the master interfacedevice 310 may be shared with other circuits, microcode, etc., that areemployed to perform other functions and operations within masterinterface device 310. According to the scope of the present application,microcode is a term employed to refer to one or more micro instructions.A micro instruction (also referred to as a native instruction) is aninstruction at the level that a unit executes. For example, microinstructions are directly executed by a reduced instruction set computer(RISC) processor. For a complex instruction set computer (CISC)processor such as an x86-compatible microprocessor, x86 instructions aretranslated into associated micro instructions, and the associated microinstructions are directly executed by a unit or units within the CISCprocessor.

Likewise, the slave interface device 311 according to the presentinvention is configured to perform the functions and operationsdisclosed herein. The slave interface device 311 comprises logic,circuits, devices, or microcode (i.e., micro instructions or nativeinstructions), or a combination of logic, circuits, devices, ormicrocode, or equivalent elements that are employed to perform thefunctions and operations according to the present invention. Theelements employed to perform these functions and operations within theslave interface device 311 may be shared with other circuits, microcode,etc., that are employed to perform other functions and operations withinslave interface device 311.

Now turning to FIG. 4, a block diagram 400 is presented showing a slaveinterface mechanism according to the present invention such as might beemployed in the grid management system 300 of FIG. 3. The diagram 400shows a metered facility 410 like the facilities 304 discussed above.The facility 410 includes an optional home area network (HAN) 411 suchas a wireless local area network (WLAN) that is used to control andmonitor various appliances (not shown) and devices (not shown) therein.An existing AMR meter (AMRM) 410 is coupled to a resource as discussedabove that is being monitored and controlled according to the presentinvention by a resource provider. A slave interface device 401substantially similar to the slave interface device 311 of FIG. 3 iscoupled to the AMRM 412 by any of the disclosed mechanisms discussedabove, that is, collar configuration, card slot configuration, orseparate configuration.

In all embodiments, the slave interface device 401 includes an AMRinterface 404 that couples the slave interface device 401 to the AMRM412 via AMR link 414. An optional power monitor 405 within the slaveinterface device 401 is coupled to the resource itself within the AMRM412 via optional power bus 425. In addition, a home area networkinterface 403 within the slave interface device 401 is coupled to theHAN 411 via a HAN wireless link 413.

The slave interface device 401 includes a slave controller 402 that iscoupled to the HAN interface 403 via bus 416, the AMR interface 404 viabus 417, and the optional power monitor 405 via bus 418. The slavecontroller 402 is also coupled to a wired communications link 419 thatcomprises one leg of a wired variable data rate star network asdiscussed above with reference to FIG. 3.

In operation, the AMR interface 404 receives data from the AMRM 412, andfrom any other AMRM (not shown) within a area of reception for the slaveinterface device 401. The AMR interface 404 provides this data to theslave controller 402 on bus 417.

The slave controller 402 is configured to communicate with acorresponding master interface device (not shown) over the wiredcommunications link 419 at a data rate prescribed by the masterinterface device. Accordingly, AMR data from the AMRM 412 and from otherAMRMs within the reception area is provided to the master interfacedevice over the wired communications link 419.

Optionally, commands from the master interface device are provided bythe slave controller 402 to the power monitor 405 via bus 418 to monitorand/or control the resource that is measured by the AMRM 412. In oneembodiment, the power monitor 405 is employed to cut on and cut off theresource as described above with reference to FIG. 3. In anotherembodiment, the power monitor 405 is additionally employed to gatherresource consumption data via bus 425 that is at a rate suitable forload signature and other forms of analysis. This data is provided to theslave controller 402 on bus 418 and is subsequently passed to the masterinterface device over the wired communication link 419. In oneembodiment, the master interface device passes all analysis datagathered to the NOC 303, and processing resources within the NOC 303 areemployed to perform the load signature and other analyses.

HAN-related commands provided by the NOC 303 are transmitted by themaster interface device over the wired communication link 419 and arecommunicated to/from the HAN 411 by the HAN interface 403 over the HANwireless link 413. These commands are used to control and monitorperformance of individual devices and appliances within the facility410.

Now turning to FIG. 5, a block diagram 500 is presented showing a masterinterface mechanism according to the present invention such as might beemployed in the grid management system 300 of FIG. 3. The diagram 500shows a metered facility 510 like the facilities 304 discussed above.The facility 510 includes an optional home area network (HAN) 511 suchas a wireless local area network (WLAN) that is used to control andmonitor various appliances (not shown) and devices (not shown) therein.An existing AMR meter (AMRM) 510 is coupled to a resource as discussedabove that is being monitored and controlled according to the presentinvention by a resource provider. A master interface device 501substantially similar to the master interface device 310 of FIG. 3 iscoupled to the AMRM 512 by any of the disclosed mechanisms discussedabove, that is, collar configuration, card slot configuration, orseparate configuration. The master interface device 501 is additionallycoupled to a high speed device (not shown) as discussed above via highspeed bus 521.

In all embodiments, the master interface device 501 includes an AMRinterface 504 that couples the master interface device 501 to the AMRM512 via ARM link 514. An optional power monitor 505 within the masterinterface device 501 is coupled to the resource itself within the AMRM512 via optional power bus 525. In addition, a home area networkinterface 503 within the master interface device 501 is coupled to theHAN 511 via a HAN wireless link 513.

The master interface device 501 includes a master controller 502 that iscoupled to the HAN interface 503 via bus 516, the AMR interface 504 viabus 517, and the optional power monitor 505 via bus 518. The mastercontroller 502 is also coupled to a wired communications link 519 thatcomprises one leg of a wired variable data rate star network asdiscussed above with reference to FIG. 3. The master controller 502 isadditionally coupled to a high speed device (HSD) interface 520 that isemployed to communicate with the NOC 303 over the existinginfrastructure 301 via high speed bus 521.

In operation, the AMR interface 504 receives data from the AMRM 512, andfrom any other AMRM (not shown) within an area of reception for themaster interface device 501. The AMR interface 504 provides this data tothe master controller 502 on bus 517.

The master controller 502 is configured to communicate withcorresponding slave interface devices (not shown) over the wiredcommunications link 519 at a data rate prescribed by the masterinterface device 501. Accordingly, AMR data from the AMRM 412, fromother AMRMs within the reception area, and from the corresponding slaveinterface devices on the wired communication link 519 is provided to themaster interface device 501. The master interface device 501 alsoprovides commands to and receives data from the corresponding slavedevices on the wired communication link 512 to perform the functions ofpower monitoring and control and home area network interface discussedabove with reference to FIG. 4.

Optionally, commands from the NOC 303 are provided by the mastercontroller 502 to the power monitor 505 via bus 518 to monitor and/orcontrol the resource that is measured by the AMRM 512. In oneembodiment, the power monitor 505 is employed to cut on and cut off theresource as described above with reference to FIG. 3. In anotherembodiment, the power monitor 505 is additionally employed to gatherresource consumption data via bus 525 that is at a rate suitable forload signature and other forms of analysis. This data is provided to themaster controller 502 on bus 518 and is subsequently passed to the NOC303 over the existing infrastructure 301 via the high speed data link521. In one embodiment, the master interface device 501 passes allanalysis data gathered to the NOC 303, and processing resources withinthe NOC 303 are employed to perform the load signature and otheranalyses.

HAN-related commands provided by the NOC 303 are examined by the mastercontroller 502 to determine if they are intended for the masterinterface device 501 or one of the corresponding slave interfacedevices. If intended for the master interface device 501, then thesecommands are provided to the HAN interface 503 via bus 516 and arecommunicated to the HAN 511 via HAN link 513. If intended for a slavedevice, then these commands are transmitted by the master interfacedevice 501 over the wired communication link 519 and are communicatedto/from a HAN within a designated slave interface device.

Now turning to FIG. 6, a block diagram 600 is presented showing awireless slave interface mechanism according to the present inventionsuch as might be employed in the grid management system 300 of FIG. 3.The diagram 600 shows a metered facility 610 like the facilities 304discussed above. The facility 610 includes an optional home area network(HAN) 611 such as a wireless local area network (WLAN) that is used tocontrol and monitor various appliances (not shown) and devices (notshown) therein. An existing AMR meter (AMRM) 610 is coupled to aresource as discussed above that is being monitored and controlledaccording to the present invention by a resource provider. A wirelessslave interface device 601 is coupled to the AMRM 612 by any of thedisclosed mechanisms discussed above, that is, collar configuration,card slot configuration, or separate configuration. The differencebetween the wireless slave interface device 601 and the wired slaveinterface device 401 of FIG. 4 is that communications between a masterdevice and slave devices within a local grid are performed over awireless communications link 624.

In all embodiments, the slave interface device 601 includes slaveinterface 621 that couples the slave interface device 601 to the AMRM612 via ARM link 614 and to other wireless slave interface devices and amaster interface device within the local grid via wireless link 624. Inthe embodiment shown, communications provided by the slave interface 621over wireless link 624 take the place of the wired communication link419 of the embodiment of FIG. 4. One embodiment of the present inventioncomprehends a wireless mesh network as the wireless link 624 accordingto protocols prescribed by IEEE 802.15.4 specifications. Anotherembodiment contemplates an IEEE 802.11 wireless network.

An optional power monitor 605 within the slave interface device 601 iscoupled to the resource itself within the AMRM 612 via optional powerbus 625. In addition, a home area network interface 603 within the slaveinterface device 601 is coupled to the HAN 611 via a HAN wireless link613.

The slave interface device 601 includes a slave controller 602 that iscoupled to the HAN interface 603 via bus 616, the slave interface 621via bus 617, and the optional power monitor 605 via bus 618.

In operation, the slave interface 621 receives data from the AMRM 612,and from any other AMRM (not shown) within an area of reception for theslave interface device 601. The slave interface 621 provides this datato the slave controller 602 on bus 617.

The slave controller 602 is configured to communicate with acorresponding master interface device (not shown) over the wirelesscommunications link 624. Accordingly, AMR data from the AMRM 612 andfrom other AMRMs within the reception area is provided to the masterinterface device over the wireless communications link 624 via the slaveinterface 621.

Optionally, commands from the master interface device received by theslave interface 621, provided to the slave controller 602 via bus 617,and are provided by the slave controller 602 to the power monitor 605via bus 618 to monitor and/or control the resource that is measured bythe AMRM 612. In one embodiment, the power monitor 605 is employed tocut on and cut off the resource as described above with reference toFIG. 3. In another embodiment, the power monitor 605 is additionallyemployed to gather resource consumption data via bus 625 that is at arate suitable for load signature and other forms of analysis. This datais provided to the slave controller 602 on bus 618 and is subsequentlypassed to the master interface device over the wireless communicationlink 624. In one embodiment, the master interface device passes allanalysis data gathered to the NOC 303, and processing resources withinthe NOC 303 are employed to perform the load signature and otheranalyses.

HAN-related commands provided by the NOC 303 are transmitted by themaster interface device over the wireless communication link 624 and arecommunicated to/from the HAN 611 by the HAN interface 603 over the HANwireless link 613. These commands are used to control and monitorperformance of individual devices and appliances within the facility610.

Turning now to FIG. 7, a block diagram 700 is presented showing awireless master interface mechanism according to the present inventionsuch as might be employed in the grid management system 300 of FIG. 3.The diagram 700 shows a metered facility 710 like the facilities 304discussed above. The facility 710 includes an optional home area network(HAN) 711 such as a wireless local area network (WLAN) that is used tocontrol and monitor various appliances (not shown) and devices (notshown) therein. An existing AMR meter (AMRM) 710 is coupled to aresource as discussed above that is being monitored and controlledaccording to the present invention by a resource provider. A wirelessmaster interface device 701 is coupled to the AMRM 712 by any of thedisclosed mechanisms discussed above, that is, collar configuration,card slot configuration, or separate configuration. The wireless masterinterface device 701 is additionally coupled to a high speed device (notshown) as discussed above via high speed bus 721.

In all embodiments, the master interface device 701 includes a masterinterface 721 that couples the master interface device 701 to the AMRM712 via ARM link 714 and to other wireless slave devices within thelocal grid via wireless link 724. Embodiments of the wireless link 724comport with those described for wireless link 624 discussed above withreference to FIG. 6.

An optional power monitor 705 within the master interface device 701 iscoupled to the resource itself within the AMRM 712 via optional powerbus 725. In addition, a home area network interface 703 within themaster interface device 701 is coupled to the HAN 711 via a HAN wirelesslink 713.

The master interface device 701 includes a master controller 702 that iscoupled to the HAN interface 703 via bus 716, the master interface 721via bus 717, and the optional power monitor 705 via bus 718. The mastercontroller 702 is additionally coupled to a high speed device (HSD)interface 720 that is employed to communicate with the NOC 303 over theexisting infrastructure 301 via high speed bus 721.

In operation, the master interface 721 receives data from the AMRM 712,and from any other AMRM (not shown) within an area of reception for themaster interface device 501. The master interface 721 provides this datato the master controller 702 on bus 717.

The master controller 702 is configured to also direct the masterinterface 721 to communicate with corresponding slave interface devices(not shown) over the wireless communications link 724. Accordingly, AMRdata from the AMRM 712, from other AMRMs within the reception area, andfrom the corresponding slave interface devices on the wirelesscommunication link 724 is provided to the master interface device 701.The master interface device 701 also provides commands to and receivesdata from the corresponding slave devices on the wireless communicationlink 724 to perform the functions of power monitoring and control andhome area network interface discussed above with reference to FIG. 5.

Optionally, commands from the NOC 303, received over the high speed bus721, are provided by the master controller 702 to the power monitor 705via bus 718 to monitor and/or control the resource that is measured bythe AMRM 712. In one embodiment, the power monitor 505 is employed tocut on and cut off the resource as described above with reference toFIG. 3. In another embodiment, the power monitor 705 is additionallyemployed to gather resource consumption data via bus 725 that is at arate suitable for load signature and other forms of analysis. This datais provided to the master controller 702 on bus 718 and is subsequentlypassed to the NOC 303 over the existing infrastructure 301 via the highspeed data link 521. In one embodiment, the master interface device 701passes all analysis data gathered to the NOC 303, and processingresources within the NOC 303 are employed to perform the load signatureand other analyses.

HAN-related commands provided by the NOC 303 are examined by the mastercontroller 702 to determine if they are intended for the masterinterface device 701 or one of the corresponding slave interfacedevices. If intended for the master interface device 701, then thesecommands are provided to the HAN interface 703 via bus 716 and arecommunicated to the HAN 711 via HAN link 713. If intended for a slavedevice, then these commands are transmitted by the master interfacedevice 701 over the wireless communication link 724 and are communicatedto/from a HAN within a designated slave interface device.

Referring now to FIG. 8, a block diagram 800 is presented depictingtopology-adaptive networking according to the present invention. Suchadaptive networking is provided for by the wired master interface device501 and wired slave interface device 601 of FIGS. 5 and 6, respectively.The diagram 800 shows a wired master interface device 801 that iscoupled to a plurality of wired slave interface devices 803 via a wiredstar network whose coupling point 811 resides within an existingpedestal 810 or similar cross-connect device. As shown in the diagram800, the physical lengths for transmission of data over various legs813-817 is varied and thus, as one skilled in the art will appreciate,transmission and reception of data is subject to transmission lineeffects that are typically unknown prior to deployment.

Accordingly, the master interface device 801 additionally includes amaster TX/RX 802 that couples the master interface device 801 to thestar network. In one embodiment, the master TX/RX 802 is disposed withinthe master controller 502. Likewise the slave interface devices 803includes corresponding slave TX/RX 804 that couple the slave interfacedevices 803 to their respective legs of the star network.

In operation, the master TX/RX 802 performs communication tests witheach of the slave interface devices 803 on the star network to determinean optimum data rate at which to operate. A communications protocolaccording to the present invention includes the capability for themaster device 801 to communicate with the slave devices 803 at aprescribed data rate, thus allowing the rate of data transfer to beincreased or decreased in order to provide for reliable transmission andreception of data over the various legs 813-817 of the network. In oneembodiment, slave TX/RX 804 within each of the slave devices 803 isconfigured to adjust their respective data rates responsive to directionfrom the master device 801.

The present inventors have observed that certain resource providers maynot be able to move forward in a retrofit of their existing AMR metersto provide the 2-way communications capabilities and other capabilitiesnoted above, yet they may desire to reduce or eliminate fleet costsassociated with gather usage data as is shown in FIG. 1. As one skilledin the art will appreciate, not only are fleet resources expensive tooperate and maintain, but because typical configurations of AMR metersimplement variants of the ERT protocol, meter reading trucks areconfigured with more expensive wideband receives that are capable ofreceiving transmissions from individual meters on any one of theavailable frequencies when the trucks are dispatched. Accordingly, oneaspect of the present invention contemplates providing a fixed networkof low cost narrowband receiving devices that implement a novel and costeffective technique for receiving and correlating AMR packets, not onlyto obtain usage data related to billing, but also to obtain real timemeter data. This real time data may be utilized by a utility or managingentity for any number of purposes and does not require the dispatch offleet resources or personnel. In one embodiment, the present inventioncomprises a network of low cost narrowband receivers which may bedeployed across a geographic area that is collocated with a plurality ofAMR meters in order to facilitate reading of the meters in a low costand reliable fashion, while also providing the capability to capture andtransport continuous broadcasts from AMR meters in order to facilitatemonitoring real time energy consumption.

Referring to FIG. 9, a block diagram 900 is presented illustrating anapparatus for receiving and transporting real time energy data accordingto the present invention. The diagram 900 depicts a plurality ofgeographically collocated facilities 901 that are each equipped with anAMR meter 902 as is described above. The apparatus includes a pluralityof low cost, tunable, narrowband receivers 903 with antennae 904 thatare deployed within the geographic area such that broadcasts from AMRpacket transmissions from each of the individual AMR meters 902 can becaptured by at least one of the antennae 904/receivers 903 on at leastone of a plurality of narrowband broadcast frequencies. In oneembodiment, the antennae 904/receivers 903 are configured to comportwith the eight pre-defined narrowband frequency channels correspondingto the ERT protocol, wherein eight identical AMR packets are transmittedon each of eight different narrowband frequencies according to afrequency hopping sequence, and wherein the AMR packets contain meteridentification along with usage data.

The receivers 903 are coupled to a controller 905 and the controller iscoupled to a network operations center (NOC) 907 via an existinginfrastructure 906 (e.g., DSL, cable, etc.) as is described above withreference to FIG. 3.

In operation, the controller 905 configures each of the receivers 903such that all of the meters 902 in the geographic area are identifiedand the frequency hopping sequence for each of the meters is determined.Thereafter, the controller 905 configured to configure each of thereceivers 903 in terms of channel assignment such that optimal coverageof the AMR meters 902 is achieved to provide for reception of real timeusage data. The controller 905 is also configured to transport this realtime usage data over the existing infrastructure to the NOC 907 viaknown mechanisms.

Advantageously, even though the hop sequence of each AMR meter 902 isnot initially known, the low cost receivers 903 according to the presentinvention are initially programmed by the controller 905 to each receiveon a different channel. Over time, the channel of each receiver 903 isrotated, such that the total channels for each geographic region aremonitored over a sufficiently long interval until all local transmitters902 have been identified. In one embodiment, the receivers 903 arenetworked and communicate a time-stamped value of each AMR packet thatthey receive to the controller 905. The controller 905 is thus enabledto discover local transmitters 902, signal quality, hop sequence, andprobable geographic location of each of the transmitters 902. Once thetransmitters 902 are mapped with respect to hop sequence, location, andsignal quality, the controller 905 then directs the network of receivers903 to monitor the most efficacious channels providing optimal coveragein order to improve network reliability. Advantageously, the presentinvention provides significant improvements over a single, centrallylocated multiband receiver in terms of reduced cost, increased long termsignal quality, increased redundancy, providing the capability toidentify probable locations of transmitters 902, and eliminating arequirement for any a-priori knowledge of hop sequence.

Turning to FIG. 10, a flow diagram 1000 is presented depicting a methodemployed by the apparatus of FIG. 9 to identify meters 902 based uponreceived AMR messages. Flow begins at block 1002 where a configurationof antennae 904/receivers 903 are deployed in a geographic area asdiscussed with reference to FIG. 9. Flow then proceeds to block 1004.

At block 1004, the controller 905 selects a next frequency channel froma pre-programmed list of channels. Flow then proceeds to block 1006.

At block 1006, the controller 905 directs all of the receivers 903 tochange reception frequency to the channel selected at block 1004. Flowthen proceeds to block 1008.

At block 1008, the receivers 903 receive any AMR packets that aretransmitted by the AMR meters 902 on the selected channel and thesepackets are forwarded to the controller 905. Flow then proceeds to block1010.

At block 1010, the controller 905 decodes the packets and extracts themeter ID data that was transmitted. The controller 905 creates/updates ameter ID list for the associated receivers 903 that obtained the packetson the selected channel. Flow the proceeds to decision block 1012.

At decision block 1012, an evaluation is made to determine if there aremore channels to scan in the channel list. If not, then flow proceeds toblock 1014. If so, then flow proceeds to block 1004.

At block 1014, the method completes.

Now referring to FIG. 11 a flow diagram 1100 is presented featuring amethod employed by the apparatus of FIG. 9 to determining a hop sequencefor meters 902 identified by the method of FIG. 10. The method begins atblock 1102 where a controller 905 according to the present inventiongenerates a meter ID list according to the method of FIG. 10. Flow thenproceeds to block 1104.

At block 1104, the controller 905 selects a meter ID from the generatedmeter ID list. Flow then proceeds to block 1106.

At block 1106, receivers 903 that can receive the selected meter ID areselected. Flow then proceeds to block 1108.

At block 1108, each of the selected receivers 903 are configured by thecontroller 905 to receive AMR packet broadcasts on different frequencychannels. Flow then proceeds to block 1110.

At block 1110, the selected receivers 903 receive the AMR packetbroadcasts for the selected meter ID on their respective differentfrequency channels. Flow then proceeds to block 1112.

At block 1112, the controller 905 records a timestamp for each of theAMR packet broadcasts received at block 1110. Flow then proceeds todecision block 1114.

At decision block 1114, an evaluation is made to determine if there aremore channels that remain in the channel list. That is, the evaluationis made in the case where there more channels to monitor than there aredeployed receivers 903. If not, then flow proceeds to block 1116. If sothen flow proceeds to block 1108.

At block 1116, since all channels have been monitored and receivedpackets time stamped, the controller 905 generates a hop sequence forthe meter ID selected at block 1104. Flow then proceeds to decisionblock 1118.

At decision block 1118, an evaluation is made to determine if there aremore meters 902 that remain in the meter ID list which have not beenmapped for hop sequence. If so, then flow proceeds to block 1104. Ifnot, then flow proceeds to block 1120.

At block 1120, the method completes.

FIG. 12 is a flow diagram showing a method employed by the apparatus ofFIG. 9 for assigning receiver channels in order to ensure optimal metercoverage. Flow begins a block 1202 where a configuration of receivers903 and a controller 905 according to the present invention beginreception of AMR packet broadcasts for meters 902 identified via themethod of FIG. 10 and whose hop sequences have been determined by themethod of FIG. 11. Flow then proceeds to block 1204.

At block 1204, a next receiver 903 is selected from a list of receivers903 corresponding to the configuration. The list of receivers 903includes a priority associated with each meter 902 based upon the numberof receivers 903 that can receive AMR packet broadcasts therefrom. Flowthen proceeds to block 1206.

At block 1206, the controller 905 determines the number of meters 902that can be read by the selected receiver 903. Flow then proceeds toblock 1208.

At block 1208, the hop sequence for each readable meter 902 isdetermined based upon the results of the method of FIG. 11. Flow thenproceeds to block 1210.

At block 1210, a frequency channel that is used by the hop sequence ofthe largest number of meters 902 that were determined at block 1206 isselected. Flow then proceeds to block 1212.

At block 1212, the controller 905 directs the selected receiver 903 tobegin receiving on the selected channel. Flow then proceeds to decisionblock 1214.

At decision block 1214, an evaluation is made to determine if allreceivers 903 in the configuration have been assigned a frequencychannel. If not, then flow proceeds to block 1204. If so, then flowproceeds to decision block 1216.

At decision block 1216, an evaluation is made by the controller 905 todetermine if there is sufficient coverage from all receivers 903 toaddress all of the meters 902 in the configuration. If so, then flowproceeds to block 1220. If not, then flow proceeds to block 1218.

At block 1218, the priority of the insufficiently covered receivers 903is raised and a meter priority list is updated. Flow then proceeds toblock 1204.

At block 1220, the method completes.

In view of potential applications of the present invention as discussedabove with reference to FIGS. 3-12, the present inventors have notedthat certain configurations of wireless devices may require varyinglevels of security associated with both installation and commissioning.As is well known in the art, most present day wireless deviceconfigurations utilize geographic proximity as a simple go/no-godiscriminator for purposes of device installation and commissioning, andthese configurations furthermore typically utilize the same level ofsecurity (e.g., algorithm and key length) across all levels ofproximity. The present inventors have observed that the present dayapproach is cumbersome for both device commissioning and normalinteraction. Accordingly, the present invention provides an apparatusand method for location base wireless security that employs knowledgeabout the proximity of wireless devices to create a tiered securitystrategy. That is, devices within close proximity are allowed tocommunicate with minimal security provisions (e.g., algorithm choice,key type and length, and etc.), while increasingly distant wirelessdevices are configured to communicate with increasingly more securityprovisions. In one embodiment, when network propagation metrics areknown, the present invention provides for scalable security provisionssuch that different network communication types (e.g., wireless star,mesh multi-hop, wired) can dynamically configure tiered security keys.

Advantageously, by creating a tiered approach to secure communicationsbetween devices based upon proximity metrics and/or locationinformation, communication between these devices can be accomplished ina more natural way, just as a computer in a living room has lesssecurity access restrictions to users inside a room than for thoseoutside of the room. Not only is the present invention well suited fornetworks of devices that are portable and mobile, but it is alsoapplicable to networks of devices that require commissioning andconfiguration in-situ. One embodiment of the present inventioncomprehends a system for security in a wireless network, where deviceswithin the network utilize geographic location information todynamically select an appropriate level of security. In this manner,devices that are known to be in closer proximity are configured withreduced security requirements. As the devices in the network becomephysically separated, the security requirements are appropriatelyescalated.

Turning now to FIG. 13, a block diagram is presented illustrating aproximity based wireless security mechanism 1300 according to thepresent invention. The mechanism 1300 includes a plurality of wirelessdevices 1301, some of which are in close proximity within a localsecurity zone 1304, some of which are in farther proximity within anintermediate security zone 1305, some of which are within distantproximity within a remote security zone 1306. An uninstalled device 1303is shown to be outside all three security zones 1304-1306. The mechanism1300 includes an access controller 1302 that is responsible formonitoring the proximity of each of the devices 1301, 1303within/without the zones 1304-1306, and that configures each of thedevices 1301, 1303 with security provisions (including denial of access)commensurate with their corresponding zone 1304-1306. Although theaccess controller 1302 is shown dispose in the intermediate zone 1305,the present inventors note that such a controller 1302 may be disposedin any zone 1304-1306 or removed therefrom where provisions exist forcommunications between the controller 1302 and the devices 1301, 1303.

Operationally, the controller 1302 configures devices 1301 in the localzone 1304 to implement security provisions as discussed above that areminimal. The controller 1302 configures devices 1301 in the intermediatezone 1305 to implement increased security provisions. And devices 1301in the remote security zone 1306 are configured by the controller 1302to implement more security provisions than those devices 1301 in theintermediate zone.

Because the uninstalled device 1303 falls outside the defined securityzones, the controller 1302 precludes it from joining the network.

Although only three security zones 1304-1306 are depicted, the presentinventors note that such is shown for clarity sake and there presentinvention contemplates any number of security zones having successivelyincreased levels of security provisions for devices disposed therein.

Now referring to FIG. 14, a flow diagram 1400 is presented detailing atechnique employed by the security mechanism of FIG. 13 to allow orprevent devices from joining a network. Flow begins at block 1402 wherea controller 1302 according to the present invention monitors access andproximity of devices 1301 within the network. Flow then proceeds todecision block 1404.

At decision block 1404, the controller 1302 monitors for requests byuninstalled devices 1303. If there are none, then flow proceeds todecision block 1404. If so, then flow proceeds to decision block 1406.

At decision block 1406, the controller 1302 determines if theuninstalled device 1302 is capable of providing geographic position data(e.g., GPS data). If so, the flow proceeds to decision block 1410. Ifnot, then flow proceeds to block 1408.

At block 1408, the controller determines the relative location of theuninstalled device 1303 by issuing ping messages and evaluating responselatencies associated therewith. For example, if ping responses exhibitlatencies commensurate with those devices 1301 in the intermediatesecurity zone 1305, then the uninstalled device 1303 is determined bythe controller to be in the intermediate security zone 1305 as well.Flow then proceeds to decision block 1410.

At decision block 1410, the controller 1302 determines if theuninstalled device 1303 meets locality criteria for any of thepre-defined security zones 1304-1306. If so, the flow proceeds to block1416. If not, then flow proceeds to decision block 1412.

At block 1412, the controller 1302 determines if the uninstalled device1303 possesses a security key for the zone requested by the device 1303.If not, then flow proceeds to block 1414. If so, then flow proceeds toblock 1416.

At block 1414, the device 1303 is precluded from joining the network andflow proceeds to block 1418.

At block 1416, the device 1303 is allowed to join the network and flowproceeds to block 1418.

At block 1418, the method completes.

The present inventors have additionally noted that understanding thetopology and communication behavior of a mesh network, such as thenetwork discussed with reference to FIGS. 3-8, is difficult, butimportant. Each installation provides unique challenges in topologies,interference, and control points. A mesh network's response in reactionto these challenges is different as well. Installers and designers oftenbecome interested with the connectivity of networks as a consequence.Unlike a traditional wired installation, wireless topology and behavioris not something that can be easily seen and verified. And manufacturershave invested heavily in the development of mesh network analysis tools,yet these tools are more often than not too complex for installers tounderstand and effectively use.

Consequently, the present inventors have observed that one of thefigures of merit affecting the performance of a mesh networkinstallation is the number of hops from a central point to any endpoint.Accordingly, one aspect of the present invention focuses on how amessage propagates between routers in the network before arriving at adestination device. A great cost savings occurs in the installation ofnetworks where it is discovered that there are fewer hops than there arerouters because the unnecessary routers can be removed and reused.

In order to determine the topology of a given network, most analysistools clog the network with link status messages between devices andthen backhaul diagnostic traffic packets to a collector that can displaythis information. But it is noted that such an approach is limiting inthat the “analysis” traffic introduces an artificial load and type intothe network, while also impeding normal operation.

The present invention removes these complexities in measurement byintroducing a selectable store-and-forward delay in the operation ofeach router in a network of devices. By creating a substantial delay ineach routed hop in the network, the hops needed to route a messagebetween source and destination can easily be measured. In oneembodiment, the store-and-forward delay is orders of magnitude largerthan that normally introduced by message propagation and internalrouting software. In one embodiment, the routing delays are programmableand provide for the creation of measurable latency in messages sentbetween a source device and a destination device. This latency isanalyzed in order to ascertain the routers that are participating in themessage routing, and to understand the topology of a complex network.Because the routing delays are much greater than normal propagationdelays, the network according to the present invention is not affectedby the introduction of this additional traffic.

This present invention introduces programmable delays inside a router(i.e., any device that routes messages as part of a multi-hop network)in order to delay forwarded (routed) messages. Accordingly, the responselatency between a source device and a destination device can beascertained because it correlates with the sum of delays programmed intothe routers that are participating in the message routing.

Now referring to FIG. 15, a block diagram is presented showing a meshnetwork topology assessment mechanism 1500 according to the presentinvention. The assessment mechanism 1500 includes a plurality of routers1506, each of which include a store-forward controller 1502. Themechanism 1500 also includes and originating device 1503 and adestination device 1504. Each of the store-forward controllers 1502 canbe programmed with a unique routing delay.

In operation, once all of the routers 1501 are programmed withassociated routing delays, the originating device 1503 transmits amessage MSG to the destination device 1504. The message MSG isinterpreted by the routers 1501 in the hop chain—in the diagram shown asROUTER C 1501 and ROUTER D 1501—which each introduce the delay that isprogrammed into their respective store-forward controllers 1502, and themessage MSG is delivered to the destination device 1504. The destinationdevice responds with a link assessment acknowledge message ACK, whichreturns through the hop chain to the originating device 1503, where thestore-forward controllers 1502 in the routers 1501 in the hop chainintroduce the programmed delays into the propagation path of the ACK. Inone embodiment, the return hop chain for the ACK may be different thanthe forward hop chain for the message MSG and the delays provided for bythe store-forward controllers 1502 are uniquely selected such that itthe propagation path and network topology can be clearly discerned fromthe cumulative round trip propagation time.

The routers 1501 according to the present invention are configured toperform the operations and functions as is described above. The routers1501 comprise logic, circuits, devices, or microcode (i.e., microinstructions or native instructions), or a combination of logic,circuits, devices, or microcode, or equivalent elements that areemployed to perform the operations and functions described above. Theelements employed to perform these operations and functions may beshared with other circuits, microcode, etc., that are employed toperform other functions within the routers 1501.

Turning to FIG. 16, a flow diagram 1600 is presented depicting a methodemployed by the mechanism of FIG. 15 to assess the topology of a meshnetwork, as seen from the level of a particular router 1501. Flow beginsat block 1602, where a network of routers 1501 according to the presentinvention are deployed with store-forward controllers 1502 havingrouting delays programmed therein. An originating device 1503 sends amessage to a destination device 1504. Flow then proceeds to decisionblock 1604.

At decision block 1604, the router 1501 monitors for incoming messages.If there are none, then flow proceeds to decision block 1604. If anincoming message is detected, then flow proceeds to decision block 1606.

At decision block 1606, the message is parsed to determine if themessage is destined for another device. If so, then flow proceeds todecision block 1610. If not, then flow proceeds to decision block 1608.

At decision block 1610, an evaluation is made to determine if the otherdevice is in the instant router's routing table. If not, then flowproceeds to decision block 1604. If so, then flow proceeds to decisionblock 1614.

At decision block 1614, the router 1501 determines if a link assessmentmode is active. If so, then flow proceeds to block 1618. If not, thenflow proceeds to block 1620.

At block 1618, since link assessment is active, the router 1501 delaysthe message by the programmed delay time, and then forwards the messageto the next hop towards the destination device 1504. Flow then proceedsto block 1626.

At block 1620, since link assessment is not active, the router 1501forwards the message to the next hop towards the destination device1504. Flow then proceeds to block 1626.

At decision block 1608, it is determined if the destination of themessage is the instant router 1501. If not, then flow proceeds todecision block 1604. If so, then flow proceeds to block 1612.

At block 1612, the message is received by the instant router and parsed.Flow then proceeds to decision block 1616.

At decision block 1616, it is determined if the message is a linkassessment control message. If not, then flow proceeds to block 1622. Ifso, then flow proceeds to block 1624.

At block 1622, the message is processed. Flow then proceeds to block1626.

At block 1624, the link assessment state and corresponding link delayare set in the store-forward controller 1502 as directed by the linkassessment control message. Flow then proceeds to block 1626.

At block 1626, the method completes.

As one skilled in the art will appreciate, a present day low powerwireless network overcomes the power and range limitations of low powerdevices by allowing the messages to “hop,” that is to be retransmittedby multiple intermediary devices in order to deliver a message to adistant recipient. And most assessments of transmission quality stillutilize a signal strength indication for each individual hop, which doesnot necessarily correlate to the quality of all hops necessary totransport the messages from source to destination. The present inventorshave further observed that it is not only desirable to understand thetopology and communication behavior of a mesh network, such a thenetwork discussed with reference to FIGS. 3-8 and 16-17, but it is alsoadvantageous to understand end-to-end link quality of the network,similar to that presently provided for in a conventional hop-to-hopreceived signal strength indication (RSSI). Accordingly, one aspect ofthe present invention contemplates a mechanism for creating a morecomposite end-to-end link quality indication by aggregating the per-hopsignal strength indications (RSSI) into a single term that may be usedto support network decisions that are based on complete round-triptransmissions in a multi-hop network. Advantageously, the presentinvention improves the ability of system designers and devices tounderstand the true end-to-end quality of a message transmitted in amulti-hop network. By aggregating the per-hop RSSI value typicallystored at each device into a single value representative of the totalround-trip quality of the message and subsequent acknowledgment, a moreaccurate assessment can be made of the propagation of messages in anetwork. This technique results in improved operation, improveddiagnostics capability, and reduced installation/configuration costs.

Turning now to FIG. 17, a block diagram 1700 is presented illustrating atechnique according to the present invention for determining a networklevel received signal strength indication (RSSI). The diagram 1700depicts a plurality of wireless routers 1701 deployed within thenetwork. Each of the routers 1701 includes RSSI logic 1702. Anoriginating device 1703 is wirelessly coupled to Router A 1701 and adestination device 1704 is wirelessly coupled to Router C 1701. Adisplay is 1705 is coupled to the destination device 1704.

In operation, the originating device 1703 starts a process of testingthe end-to-end link quality of the multi-hop network and by sendingmessages to the destination device 1704, and the display 1705 isemployed to indicate an aggregated end-to-end RSSI value. A plurality ofping messages PING and pong messages PONG are sent through the networkin order to determine the end-to-end RSSI value. The originating device1703 sends a ping message PING, and each intermediary device 1701 in thenetwork receives the message, adds RSSI information to a correspondingfield R1-R4 of the message PING, and forwards the message PING to thedestination device 1704. The destination device 1704 receives themessage PING and returns a pong response message PONG. The response PONGis propagated through the network, where each intermediary device 1701continues to add RSSI information R5-R8. When the pong message PONG isreceived by the originating device 1703, the RSSI information R1-R8 isexamined, a composite end-to-end RSSI value is generated by theoriginating device 1703, and this composite value is included in amessage DISPDATA to the destination device 1704. The composite RSSIvalue is transmitted to the display 1705 to facilitate installation ofthe destination device 1705 in a location with adequate end-to-endsignal quality. One embodiment of the present invention contemplatessingle end-to-end RSSI value to indicate end-to-end link quality.Another embodiments consider use of the same mechanism to represent linkquality in a different or more complex way, such as by displaying boththe number of hops in a network as well as a forward link (i.e., PING)RSSI end-to-end RSSI value and a reverse link (i.e., PONG) end-to-endRSSI value. In one embodiment, individual hop-to-hop RSSI values R1-R8are indicated as a range of signal strength from 0-255, and thecomposite RSSI value generated by the originating device 1703 is theaverage of the hop-to-hop values. An alternative embodiment contemplatesgeneration of the composite RSSI value as a weighted average of theindividual hop values, where the weights for each hop are determinedbased upon system performance and/or cost criteria.

While the low cost mechanism for receiving and transporting real timeenergy data described above with reference to FIGS. 9-12 enables theallocation of receiver resources to optimally cover a plurality of AMRmeters having an unknown hopping sequence, it is noted that suchallocation does not precisely detect each adjacent frequency hop that istaken by an individual AMR meter, but rather takes into account that thesame data is transmitted by the individual AMR meter at the differentfrequency hops according to an unknown hop algorithm. Accordingly, thereceiver resources are assigned to best utilize a plurality of receiversthat are set to different frequency bands. And while such a technique isuseful for reading of AMR meters where the same data is transmitted oneach of a plurality of frequency hops, the present inventors have notedthat it may be desirable to ascertain a specific frequency hoppingsequence employed by frequency hopping devices. They have furtherobserved that by utilizing a systematic approach to examiningfrequencies and transmissions that are employed by a hopping network,the specific frequency hopping sequence can be determined for thosenetworks whose hopping algorithm is a linear function of time. Since thetime between hops is deterministic, it is possible to examine sets ofchannels to identify “adjacent channels” in the hopping list. Byexamining the sets of channels over time, the adjacent channels areidentified and the entire list is correlated, thereby yielding thespecific frequency hopping sequence.

Accordingly, the present invention provides for the determination of thespecific frequency hopping sequence for a frequency hopping network ordevice without prior knowledge of the algorithm and/or sequence. Thepresent invention may be employed as part of a network of devices thatreceive AMR meter broadcasts and forward the real time meter energyreadings to a facility, such as a utility or NOC, thus creating a “smartmeter” network from pre-existing AMR meters.

Those skilled in the art will appreciate that a hopping sequence may bedetermined through the use of costly broadband multi-channel radios, bysequentially scanning a list of frequencies, or by employing otherbrute-force methods. In contrast, the present invention contemplatesdetermining a hop sequence by progressively selecting channel candidatesbased on latency of messages observed between channels. For instance, ina network where the hop rate is fixed, it follows then that the latencyof messages being transmitted across multiple hops should be at aminimum between two channels adjacent to each other in the hoppingsequence. Stated differently, two channels are selected, and the latencyof messages occurring between the two channels is measured. If thelatency measured is that of the fixed hop rate, then those two channelsare considered adjacent, with the later message arriving at the latestchannel in the list. By progressively monitoring two channels in a listof channels, a sequence list can be built that describes the hoppingsequence of the network.

Referring to FIG. 18, a flow diagram 1800 is presented depicting amethod according to the present invention for discovering the frequencyhopping sequence corresponding to a network of devices. Flow begins atblock 1802 where a tunable receiver is deployed to receive messagestransmitted by devices in the network. Flow then proceeds to block 1804.

At block 1804, a channel is selected from a channel list and thereceiver is tuned to the selected channel. Flow then proceeds todecision block 1808.

At decision block 1808, the receiver determines if a message on theselected channel has been received before a timeout corresponding to apredicted hop interval. If so then flow proceeds to block 1812. If notthen flow proceeds to block 1810.

At block 1810, the selected channel is marked as an unknown channel andflow proceeds to decision block 1814.

At block 1812, the selected channel is recorded as a used channel andthe time of reception of determined in decision block 1808 is recorded.Flow then proceeds to decision block 1814.

At decision block 1814, the receiver performs an evaluation to determineif there are any channels remaining in the channel list that haveunknown adjacent channels. If not, then flow proceeds to block 1826. Ifso, then flow proceeds to block 1816.

At block 1816, the receiver selects another channel from the channellist. Flow then proceeds to block 1820.

At block 1820, the receiver determines if a message on the selectedother channel has been received before a timeout corresponding to apredicted hop interval. If so then flow proceeds to decision block 1822.If not then flow proceeds to block 1816.

At decision block 1822, the receiver determines if the latency betweenthe previous two channel transmissions is equal to the expected hopinterval. If not then flow proceeds to block 1816. If so, then flowproceeds to block 1824.

At block 1824, the two previous channels are added to a hop list andflow proceeds to block 1806.

At block 1806, a channel with unknown adjacent channels in the hop listis selected and flow proceeds to decision block 1808.

At block 1826, the method completes.

The present inventors have further observed that in many wirelessnetworks it may be necessary to transmit very large payloads to deviceswithin the network, thus resulting in burdensome traffic. Consider oneexample of a large payload, in the case where, say, a software updatemust be sent to all of the devices within the network. As one skilled inthe art will appreciate, virtually all present day wireless protocolstoday require fragmentation of a large payload into a series of smallerpayloads that can each be transmitted in a single packet. The presentinventors have noted, though, for devices that are able to utilizemultiple simultaneous bands or channels to receive messages, such as thedevices discussed above with reference to FIGS. 3-18, it may bedesirable to fragment a large payload and to simultaneously transmitfragments of the payload over different bands. One embodiment of thepresent invention comprehends a technique for fragmenting (“segmenting”)a large payload such that a first band/channel transmits the fragmentsof the payload sequentially starting from a first fragment and ending ata last fragment. Simultaneously on a second band/channel, the sameentire payload is transmitted in reverse order, starting at the lastfragment and ending at the first fragment. A receiving device monitorsthe fragments that are received on the first and second bands/channels,and when the fragments overlap (i.e., the same fragment is received byover both the first and second bands/channels, the receiving deviceconsiders the complete payload as having been received, and reassemblesthe entire payload from the received fragments. Advantageously, thetotal time required to transmit a large payload is reduce andband/channel utilization improves. In one embodiment, since differentfrequency bands may utilize different transmission rates, packet sizes,and energy requirements, payload fragmentation can be optimized toprovide the transmission of the complete payload in a minimum time.Another embodiment contemplates fragmentation that is optimized tominimize required amount of energy consumed to transfer the entirepayload. A further embodiment comprehends transmitting and receivingdevices having more than two bands/channels, where fragmentation of theentire message is executed to accomplish overlap (i.e., completereception) based upon minimum time, minimum energy, or other factorssuch as hop cost.

FIG. 19 is a block diagram 1900 featuring an apparatus according to thepresent invention for simultaneously fragmenting and transmitting largepacket payloads. The diagram shows a transmitting device 1901 and areceiving device 1911. Each of the devices 1901, 1911 include a firsttransceiver 1902, 1912 that transmits and receives data over a firstband/channel, and a second transceiver 1903, 1913 that transmits andreceives data over a second band/channel. Each of the devices 1901, 1911also include fragmentation logic 1904, 1914 that is coupled to the firstand second transceivers 1902, 1912, 1903, 1913, respectively. Also shownis a large payload 1905, 1915 that is to be transmitted and received asdescribed above.

In operation, for transmission, fragmentation logic 1904 in thetransmitting device 1901 provides the large payload 1905 to the firsttransceiver 1902 such that the first transceiver 1902 transmits thefragments 1905.A-1905.B of the payload sequentially starting from afirst fragment 1905.A and ending at a last fragment 1905.B.Simultaneously, fragmentation logic 1904 in the transmitting device 1901provides the large payload 1905 to the second transceiver 1903 such thatthe second transceiver 1903 transmits the fragments 1905.A-1905.B of thepayload sequentially starting from the last fragment 1905.6 and endingat the first fragment 1905.A.

Transmissions are received by the first and second transceivers 1912,1913 in the receiving device 1911 and the fragmentation logic 1914 inthe receiving device 1911 reassembles the large payload 1915 assequentially increasing segments are received by the first transceiver1912 and as sequentially decreasing segments are received by the secondtransceiver 1913. When received segments overlap, the fragmentationlogic 1914 considers the large payload 1915 as having been received andmay direct the receiving device 1911 to take other actions (such assending a large payload early termination acknowledgement message) asthe host protocol allows.

It is noted that the grid management system described above withreference to FIGS. 3-8 includes a network of devices which are employedto provide for automatic meter reading (AMR) and to control a home areanetwork (HAN) for the control and monitoring of various devices andappliances within a facility. Furthermore, embodiments of the network ofdevices are disclosed where communications between the devices isaccomplished over a wireless mesh network, including those comportingwith IEEE 802.15.4 and IEEE 802.11 protocols. Yet, the present inventorshave observed that while the IEEE 802.15.4 and IEEE 802.11 protocolspecifications define multiple frequency bands, and the characteristicsfor signaling in those bands, there are no defined mechanisms fordynamic band selection. Additionally the present inventors note thatmany standards, such as those describing ZIGBEE® and IEC 62591 (alsoknown as WirelessHART®) protocols, discuss proposed mechanisms forutilizing multiple channels within a band, but they do not prescribetechniques for dynamically selecting frequency bands on a per-packetbasis, where the packets may have varying communication characteristicssuch as bit rate, packet size, range, and power efficiency. In networkscomprising devices that are able to communicate across multiple bands,the present inventors have observed that it is advantageous todynamically select and utilize multiple frequency bands forcommunication in order to improve communication propagationcharacteristics, message delivery reliability, and immunity frominterference. Accordingly, one aspect of the present inventioncontemplates the use of acknowledgement (ACK) response metrics todynamically select appropriate frequencies and bands in a multi-bandcommunications network. In addition to dynamic selection of frequenciesand bands, another aspect of the present invention may utilize ACKresponse metrics from other communications mediums over those associatedwith wireless communications to further improve the characteristics ofthe communication between a network of devices.

Referring to FIG. 20, a block diagram 2000 is presented illustrating amulti-band communication network according to the present invention. Thenetwork includes a plurality of multi-band devices 2001, 2011, 2021,2031 that communicate wirelessly over communications mediums 2040 havingvariable characteristics such as throughput, reliability, efficiency,etc. Each of the devices 2001, 2011, 2021, 2031 in the network has oneor more communication transceivers 2002-2004, 2012-2013, 2022, 2024,2033, 2034, where each transceiver 2002-2004, 2012-2013, 2022, 2024,2033, 2034 has the capability to communicate with other devices 2001,2011, 2021, 2031 having the same band capabilities. It is noted that theexample of FIG. 20 portrays a network as a group of devices 2001, 2011,2021, 2031 that communicate utilizing any and all frequencies, bands,and mediums available which are enabled by their respective transceivers2002-2004, 2012-2013, 2022, 2024, 2033, 2034. In order for anoriginating device 2001, 2011, 2021, 2031 to propagate a message to adestination device 2001, 2011, 2021, 2031, the originating device 2001,2011, 2021, 2031 must choose a transceiver 2002-2004, 2012-2013, 2022,2024, 2033, 2034 that is available on the destination device 2002-2004,2012-2013, 2022, 2024, 2033, 2034. Accordingly, the present inventorsnote that the present invention does not require all devices 2001, 2011,2021, 2031 on a network to have the same number or type of transceivers2002-2004, 2012-2013, 2022, 2024, 2033, 2034. As shown in FIG. 20, thefour illustrated devices 2001, 2011, 2021, 2031 comprise onecommunication network. In this example, in order to propagate a messagebetween two devices 2001, 2011, 2021, 2031 over the network, theoriginating device 2001, 2011, 2021, 2031 must choose a transceiver2002-2004, 2012-2013, 2022, 2024, 2033, 2034 that is known to exist onthe destination device 2001, 2011, 2021, 2031. For example, a firstdevice 2001 and a second device 2011 can communicate using the band A,B, or C transceivers 2002-2004, 2012-2014, while the first device 2001and a third device 2021 can communicate using the band A and Ctransceivers 2002, 2022, 2004, 2024, since the third device 2021 doesnot include a band B transceiver 2003. In order for the first device2001 to send a message to the third device 2021, it must choose the mostappropriate transceiver, either band A 2002 or band C 2004.

Now turning to FIG. 21, a flow diagram 2100 is presented highlighting anexemplary method according to the present invention. Suppose that onedevice is required to send a message to another device. Accordingly, theflow diagram 2100 details the process of selecting the propertransceiver to accomplish the transmission. The one device utilizesmessage descriptors (i.e., a set of defined metrics that describe therequirements for sending the message) to select a transceiver that bestmatches the those requirements. Upon receipt of an acknowledgement ofthat transmission, new ACK response descriptors would be used to updatethe transceiver and device descriptors such that a following message canselect the best transceiver available for that transmission. Flow beginsat block 2102 where a the one device is configured to send the messageto the other device. Flow then proceeds to block 2104.

At block 2104, the first device access descriptor stores therein toobtain descriptors for the message. Flow then proceeds to block 2106.

At block 2106, the one device accesses the descriptor stores to obtaindescriptors at the transceiver and device level. Flow then proceeds toblock 2108.

At block 2108, the one device selects a transceiver to send the messageto the other device based upon data obtained from the descriptor storesaccessed at blocks 2104 and 2106. Flow then proceeds to block 2110.

At block 2110, the one device transmits the message over the selectedtransceiver. Flow then proceeds to decision block 2112.

At decision block 2112, the one device determines if an acknowledge ACKis received before a timeout for retransmission has expired. If so, thenflow proceeds to block 2116. If not, then flow proceeds to decisionblock 2114.

At decision block 2114, the one device determines if a maximum number ofretries has occurred. If so, then flow proceeds to block 2118. If not,the flow proceeds to block 2110.

At block 2118, a next best transceiver is selected for transmission ofthe message, and flow proceeds to block 2110.

At block 2116, device and transceiver descriptors are updated in thedescriptor store within the one device based upon the ACK response. Flowthen proceeds to block 2120.

At block 2120, the method completes.

FIG. 22 is a block diagram detailing an exemplary descriptor stores 2200within a device according to the present invention such as may beemployed within the network of FIG. 20. The stores 2200 includes aplurality of message descriptors 2201 corresponding to a plurality ofmessages MSG 1-MSG N. The stores 2200 also includes a plurality oftransceiver descriptors 2211 corresponding to a plurality oftransceivers XCVR 1-XCV N within the device. The stores 2200 furtherinclude a plurality of device descriptors 2221 corresponding to aplurality of destination devices DEVICE 1-DEVICE N within the network.

The message descriptors 2201 include a latency requirement field 2202, amessage size field 2203, a transceiver energy available field 2204, andan other requirement field.

The transceiver descriptors 2211 include a packet delivery latency field2212, a payload size field 2213, an energy required per packet field2214, and an other attribute field 2215.

The device descriptors 2211 each have one or more transceiver attributedescriptors corresponding to a destination device DEVICE 1-DEVICE N.Each of the transceiver attribute descriptors include a transceiver IDfield 2222, a delivery reliability field 2223, an energy required perpacket field 2224, and an other attribute field 2225.

In operation, by utilizing knowledge about the capabilities andoperating characteristics of each medium, stored as a set of descriptors2201, 2211, 2221, a device according to the present invention may selecta transceiver (i.e., frequency band) that provides for optimalinteroperation with respect to energy consumption, throughput, andreliability, thus eliminating the problems inherent in single-bandnetworks, where interference from other devices and multipathinterference (over a narrow range of frequencies in a band) reduce thereliability of the network.

Portions of the present invention and corresponding detailed descriptionare presented in terms of software, or algorithms and symbolicrepresentations of operations on data bits within a computer memory.These descriptions and representations are the ones by which those ofordinary skill in the art effectively convey the substance of their workto others of ordinary skill in the art. An algorithm, as the term isused here, and as it is used generally, is conceived to be aself-consistent sequence of steps leading to a desired result. The stepsare those requiring physical manipulations of physical quantities.Usually, though not necessarily, these quantities take the form ofoptical, electrical, or magnetic signals capable of being stored,transferred, combined, compared, and otherwise manipulated. It hasproven convenient at times, principally for reasons of common usage, torefer to these signals as bits, values, elements, symbols, characters,terms, numbers, or the like.

It should be borne in mind, however, that all of these and similar termsare to be associated with the appropriate physical quantities and aremerely convenient labels applied to these quantities. Unlessspecifically stated otherwise, or as is apparent from the discussion,terms such as “processing” or “computing” or “calculating” or“determining” or “displaying” or the like, refer to the action andprocesses of a computer system, a microprocessor, a central processingunit, or similar electronic computing device, that manipulates andtransforms data represented as physical, electronic quantities withinthe computer system's registers and memories into other data similarlyrepresented as physical quantities within the computer system memoriesor registers or other such information storage, transmission or displaydevices.

Note also that the software implemented aspects of the invention aretypically encoded on some form of program storage medium or implementedover some type of transmission medium. The program storage medium may beelectronic (e.g., read only memory, flash read only memory, electricallyprogrammable read only memory), random access memory magnetic (e.g., afloppy disk or a hard drive) or optical (e.g., a compact disk read onlymemory, or “CD ROM”), and may be read only or random access. Similarly,the transmission medium may be metal traces, twisted wire pairs, coaxialcable, optical fiber, or some other suitable transmission medium knownto the art. The invention is not limited by these aspects of any givenimplementation.

The particular embodiments disclosed above are illustrative only, andthose skilled in the art will appreciate that they can readily use thedisclosed conception and specific embodiments as a basis for designingor modifying other structures for carrying out the same purposes of thepresent invention, and that various changes, substitutions andalterations can be made herein without departing from the scope of theinvention as set forth by the appended claims.

What is claimed is:
 1. An apparatus for determining a frequency hoppingsequence, the apparatus comprising: a plurality of narrowband receivers,deployed geographically within a grid, wherein each of said plurality ofnarrowband receivers is configured to receive transmissions from a leastone of a plurality of automated meter reading (AMR) meters, and whereineach of said plurality of AMR meters transmits identical data on each ofa plurality of frequency bands that are hopped according to thefrequency hopping sequence, and wherein said frequency hopping sequenceis initially unknown to said plurality of narrowband receivers, but ahop rate is known; and a controller, coupled to said plurality ofnarrowband receivers, configured to control said plurality of narrowbandreceivers such that said each of said plurality of AMR meters isidentified, and configured to control said plurality of narrowbandreceivers such that corresponding data from said each of said AMR metersis received on at least one of said plurality of frequency bands,wherein said controller determines the frequency hopping sequence byprogressively selecting channel candidate pairs from a list of channelsfor the frequency hopping sequence, and determines adjacent channelpairs in said list of channels based upon latency of messages havingsaid identical data observed between said channel candidate pairsaccording to said hop rate.
 2. The apparatus as recited in claim 1,wherein said controller steps said all of said plurality of receiversthrough all of said plurality of frequency bands to receiveidentification data from said those of said plurality of AMR meters thatthat transmit on said all of said plurality of frequency bands.
 3. Theapparatus as recited in claim 2, wherein, for one of said plurality ofAMR meters, said controller directs a set of said plurality of receiversthat can receive data from said one of said plurality of AMR meters toreceive on different ones of said plurality of frequency bands, andwherein transmissions from said one of said plurality of transmittersare time stamped to generate the frequency hopping sequence.
 4. Theapparatus as recited in claim 3, wherein said controller determines acorresponding signal quality for each of said all of said plurality ofreceivers.
 5. The apparatus as recited in claim 4 wherein saidcontroller determines a corresponding probable location for said each ofsaid all of said plurality of receivers.
 6. The apparatus as recited inclaim 5, wherein, for said each of said plurality of receivers, saidcontroller selects the frequency hopping sequence for each of said thoseof said plurality of AMR meters, and wherein said controller selectschannels for said each of said plurality of receivers that are employedby a largest number of said those of said AMR meters to provide optimalcoverage.
 7. The apparatus as recited in claim 1, further comprising: anetwork operations center (NOC), operatively coupled to said controllervia an existing infrastructure, configured to receive the real timeresource usage data from said controller.
 8. An apparatus fordetermining a frequency hopping sequence, the apparatus comprising: aplurality of narrowband receivers, deployed geographically within agrid, wherein each of said plurality of narrowband receivers isconfigured to receive transmissions from a least one of a plurality ofautomated meter reading (AMR) meters, and wherein each of said pluralityof AMR meters transmits identical data on each of a plurality offrequency bands that are hopped according to a hopping sequence, andwherein said hopping sequence is initially unknown to said plurality ofnarrowband receivers, but a hop rate is known; a controller, coupled tosaid plurality of narrowband receivers, configured to control saidplurality of narrowband receivers such that said each of said pluralityof AMR meters is identified, and configured to control said plurality ofnarrowband receivers such that corresponding data from said each of saidAMR meters is received on at least one of said plurality of frequencybands, wherein said controller determines the frequency hopping sequenceby progressively selecting channel candidate pairs from a list ofchannels for the frequency hopping sequence, and determines adjacentchannel pairs in said list of channels based upon latency of messageshaving said identical data observed between said channel candidate pairsaccording to said hop rate; and a network operations center (NOC),operatively coupled to said controller via an existing infrastructure,configured to receive the real time resource usage data from saidcontroller.
 9. The apparatus as recited in claim 8, wherein saidcontroller steps said all of said plurality of receivers through all ofsaid plurality of frequency bands to receive identification data fromsaid those of said plurality of AMR meters that that transmit on saidall of said plurality of frequency bands.
 10. The apparatus as recitedin claim 9, wherein, for one of said plurality of AMR meters, saidcontroller directs a set of said plurality of receivers that can receivedata from said one of said plurality of AMR meters to receive ondifferent ones of said plurality of frequency bands, and whereintransmissions from said one of said plurality of transmitters are timestamped to generate the frequency hopping sequence.
 11. The apparatus asrecited in claim 10, wherein said controller determines a correspondingsignal quality for each of said all of said plurality of receivers. 12.The apparatus as recited in claim 11 wherein said controller determinesa corresponding probable location for said each of said all of saidplurality of receivers.
 13. The apparatus as recited in claim 12,wherein, for said each of said plurality of receivers, said controllerselects the frequency hopping sequence for each of said those of saidplurality of AMR meters, and wherein said controller selects channelsfor said each of said plurality of receivers that are employed by alargest number of said those of said AMR meters to provide optimalcoverage.
 14. The apparatus as recited in claim 8, wherein saidplurality of frequency bands and said hopping sequence are in accordancewith the Encoded Receiver Transmitter (ERT) protocol.
 15. A method fordetermining a frequency hopping sequence, the method comprising:deploying a plurality narrowband receivers within a grid, wherein eachof the plurality of narrowband receivers is configured to receivetransmissions from a least one of a plurality of automated meter reading(AMR) meters, and wherein each of the plurality of AMR meters transmitsidentical data on each of a plurality of frequency bands that are hoppedaccording to a hopping sequence, and wherein the frequency hoppingsequence is initially unknown to said plurality of narrowband receivers,but a hop rate is known; and controlling the plurality of narrowbandreceivers such that the each of the plurality of AMR meters isidentified, and that corresponding data from the each of the AMR metersis received on at least one of the plurality of frequency bands, whereinthe controller determines the frequency hopping sequence byprogressively selecting channel candidate pairs from a list of channelsfor the frequency hopping sequence, and determines adjacent channelpairs in the list of channels based upon latency of messages having theidentical data observed between said channel candidate pairs accordingto the hop rate.
 16. The method as recited in claim 15, wherein thecontroller steps the all of the plurality of receivers through all ofthe plurality of frequency bands to receive identification data from thethose of the plurality of AMR meters that that transmit on the all ofthe plurality of frequency bands.
 17. The method as recited in claim 16,wherein said controlling further comprises: for one of the plurality ofAMR meters, directing a set of the plurality of receivers that canreceive data from the one of the plurality of AMR meters to receive ondifferent ones of the plurality of frequency bands, and whereintransmissions from the one of the plurality of transmitters are timestamped to generate the frequency hopping sequence.
 18. The method asrecited in claim 17, wherein said controller determines a correspondingsignal quality for each of the all of the plurality of receivers. 19.The method as recited in claim 18, wherein said controller determines acorresponding probable location for the each of the all of the pluralityof receivers.
 20. The method as recited in claim 19, wherein saidcontrolling further comprises: for the each of the plurality ofreceivers, first selecting the frequency hopping sequence for each ofthe those of the plurality of AMR meters, and second selecting channelsfor the each of the plurality of receivers that are employed by alargest number of the those of the AMR meters to provide optimalcoverage.
 21. The method as recited in claim 15, further comprising:transmitting the real time resource usage data to a network operationscenter (NOC) over an existing infrastructure.